Chemistry Review

Front

What does the chemical formula H₂O indicate about the elements in water?

Back

It shows the number of atoms of each element in the compound.

Front

In a molecular model, what does each sphere represent?

Back

An atom.

Front

What is a chemical change? Give an example.

Back

A chemical change involves a transformation that alters the substance's chemical structure. Example: Cooking a cake.

Front

What is a balanced chemical equation?

Back

A balanced chemical equation has equal numbers of each type of atom on both sides of the equation.

Front

What type of energy causes water to boil?

Back

Thermal energy.

Front

Define a physical change and provide an example.

Back

A physical change is a change that affects one or more physical properties of a substance. Example: Boiling water.

Front

What is the difference between an atom and a molecule?

Back

An atom is the smallest unit of an element, while a molecule is a group of two or more atoms bonded together.

Front

What is the law of conservation of mass?

Back

The law states that mass is neither created nor destroyed in a chemical reaction.

Front

What is an ion?

Back

An ion is an atom or molecule that has a net electrical charge due to the loss or gain of one or more electrons.

Front

What is a compound?

Back

A compound is a substance formed when two or more different elements are chemically bonded together.